Associative Arrays

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In computer science, an associative array, map, symbol table, or dictionary is an abstract data type composed of a collection of (key, value) pairs, such that each possible key appears at most once in the collection. An associative array differs from a “normal” array in one major way: rather than being indexed numerically (i.e. 0, 1, 2, 3, …), it is indexed by a key, or a language-like word. A Scripting.Dictionary is a standard object provided by the Microsoft ScripTing Runtime (scrrun.dll) dependency and is commonly used in VBScript, a reference to which needs to be added in order to create an object in your AutoIt project.

A dictionary object example by MHz

; Author Mhz
; Forum 
Global $vKey, $sItem, $sMsg, $oDictionary 

; Create dictionary object
$oDictionary = ObjCreate("Scripting.Dictionary")

If @error Then
    MsgBox(0, '', 'Error creating the dictionary object')
Else
    ; Add keys with items
    $oDictionary.Add ("One",    "Same"  )
    $oDictionary.Add ("Two",    "Car"   )
    $oDictionary.Add ("Three",  "House" )
    $oDictionary.Add ("Four",   "Boat"  )

    If $oDictionary.Exists('One') Then
        ; Display item
        MsgBox(0x0, 'Item One', $oDictionary.Item('One'), 2)
        ; Set an item
        $oDictionary.Item('One') = 'Changed'
        ; Display item
        MsgBox(0x20, 'Did Item One Change?', $oDictionary.Item('One'), 3)
        ; Remove key
        $oDictionary.Remove('One')
        ; 
        $oDictionary.Key ('Two') = 'Bike'
    EndIf

    Sleep(1000)

    ; Store items into a variable
    For $vKey In $oDictionary
       $sItem &= $oDictionary.Item($vKey) & @CRLF
    Next

    ; Display items
    MsgBox(0x0, 'Items Count: ' & $oDictionary.Count, $sItem, 3)

    ; Add items into an array
    $aItems = $oDictionary.Items

    ; Display items in the array
    For $i = 0 To $oDictionary.Count -1
        MsgBox(0x0, 'Items [ ' & $i & ' ]', $aItems[$i], 2)
    Next

    Sleep(1000)

    ; Add keys into an array
    $aKeys = $oDictionary.Keys

    ; Display keys in the array
    For $i = 0 To $oDictionary.Count -1
        MsgBox(0x0, 'Keys [ ' & $i & ' ]', $aKeys[$i], 2)
    Next
EndIf



The original AutoIt Scripting Dictionary implementation appears to have been by Gary Frost as far back as 2007. It has since been modified to the following:

#cs
	Scripting Dictionary UDF

	Made by GaryFrost <https://www.autoitscript.com/forum/topic/47048-scripting-dictionary/>
	Modified by Jefrey <jefrey[at]jefrey.ml>
	
	Forum https://www.autoitscript.com/forum/topic/182334-scripting-dictionary-modified/
	
#ce

Func _InitDictionary()
	Return ObjCreate("Scripting.Dictionary")
EndFunc   ;==>_InitDictionary

; Adds a key and item pair to a Dictionary object.
Func _AddItem($oDictionary, $v_key, $v_item)
	$oDictionary.ADD($v_key, $v_item)
	If @error Then Return SetError(1, 1, -1)
EndFunc   ;==>_AddItem

; Returns true if a specified key exists in the Dictionary object, false if it does not.
Func _ItemExists($oDictionary, $v_key)
	Return $oDictionary.Exists($v_key)
EndFunc   ;==>_ItemExists

; Returns an item for a specified key in a Dictionary object
Func _Item($oDictionary, $v_key)
	Return $oDictionary.Item($v_key)
EndFunc   ;==>_Item

; Sets an item for a specified key in a Dictionary object
Func _ChangeItem($oDictionary, $v_key, $v_item)
	$oDictionary.Item($v_key) = $v_item
EndFunc   ;==>_ChangeItem

; Sets a key in a Dictionary object.
Func _ChangeKey($oDictionary, $v_key, $v_newKey)
	$oDictionary.Key($v_key) = $v_newKey
EndFunc   ;==>_ChangeKey

; Removes a key, item pair from a Dictionary object.
Func _ItemRemove($oDictionary, $v_key)
	$oDictionary.Remove($v_key)
	If @error Then Return SetError(1, 1, -1)
EndFunc   ;==>_ItemRemove

; Returns the number of items in a collection or Dictionary object.
Func _ItemCount($oDictionary)
	Return $oDictionary.Count
EndFunc   ;==>_ItemCount

; Returns an array containing all the items in a Dictionary object
Func _GetItems($oDictionary)
	Return $oDictionary.Items
EndFunc   ;==>_GetItems

Func _Clear($oDictionary)
	Return $oDictionary.RemoveAll
EndFunc